#!/bin/bash
#
# chkconfig: 345 99 05 
# description: Java deamon script
#
# A non-SUSE Linux start/stop script for Java daemons.
#
# Derived from -
# Home page: http://www.source-code.biz
# License:   GNU/LGPL (http://www.gnu.org/licenses/lgpl.html)
# Copyright 2006 Christian d'Heureuse, Inventec Informatik AG, Switzerland.
#
# History:
# 2010-09-21 Josh Davis: Changed 'sudo' to 'su', fix some typos, removed unused variables
# 2009-03-04 Josh Davis: Ubuntu/Redhat version.
# 2006-06-27 Christian d'Heureuse: Script created.
# 2006-07-02 chdh: Minor improvements.
# 2006-07-10 chdh: Changes for SUSE 10.0.


# Set this to your Java installation
JAVA_HOME=/usr/java/latest

serviceNameLo="myservice"                                  # service name with the first letter in lowercase
serviceName="MyService"                                    # service name
serviceUser="appuser"                                      # OS user name for the service
serviceGroup="appgroup"                                    # OS group name for the service
applDir="/var/lib/$serviceNameLo"                          # home directory of the service application
serviceUserHome="/home/$serviceUser"                       # home directory of the service user
serviceLogFile="/var/log/$serviceNameLo.log"               # log file for StdOut/StdErr
maxShutdownTime=15                                         # maximum number of seconds to wait for the daemon to terminate normally
pidFile="/var/run/$serviceNameLo.pid"                      # name of PID file (PID = process ID number)
javaCommand="java"                                         # name of the Java launcher without the path
javaExe="$JAVA_HOME/bin/$javaCommand"                      # file name of the Java application launcher executable
javaArgs="-jar $applDir/myservice.jar"                     # arguments for Java launcher
javaCommandLine="$javaExe $javaArgs"                       # command line to start the Java service application
javaCommandLineKeyword="myservice.jar"                     # a keyword that occurs on the commandline, used to detect an already running service process and to distinguish it from others

# Makes the file $1 writable by the group $serviceGroup.
function makeFileWritable {
local filename="$1"
touch $filename || return 1
chgrp $serviceGroup $filename || return 1
chmod g+w $filename || return 1
return 0; }

# Returns 0 if the process with PID $1 is running.
function checkProcessIsRunning {
local pid="$1"
if [ -z "$pid" -o "$pid" == " " ]; then return 1; fi
if [ ! -e /proc/$pid ]; then return 1; fi
return 0; }

# Returns 0 if the process with PID $1 is our Java service process.
function checkProcessIsOurService {
local pid="$1"
if [ "$(ps -p $pid --no-headers -o comm)" != "$javaCommand" ]; then return 1; fi
grep -q --binary -F "$javaCommandLineKeyword" /proc/$pid/cmdline
if [ $? -ne 0 ]; then return 1; fi
return 0; }

# Returns 0 when the service is running and sets the variable $pid to the PID.
function getServicePID {
if [ ! -f $pidFile ]; then return 1; fi
pid="$(<$pidFile)"
checkProcessIsRunning $pid || return 1
checkProcessIsOurService $pid || return 1
return 0; }

function startServiceProcess {
cd $applDir || return 1
rm -f $pidFile
makeFileWritable $pidFile || return 1
makeFileWritable $serviceLogFile || return 1
cmd="nohup $javaCommandLine >>$serviceLogFile 2>&1 & echo \$! >$pidFile"
su -m $serviceUser -s $SHELL -c "$cmd" || return 1
sleep 0.1
pid="$(<$pidFile)"
if checkProcessIsRunning $pid; then :; else
echo -ne "\n$serviceName start failed, see logfile."
return 1
fi
return 0; }

function stopServiceProcess {
kill $pid || return 1
for ((i=0; i<maxShutdownTime*10; i++)); do
checkProcessIsRunning $pid
if [ $? -ne 0 ]; then
rm -f $pidFile
return 0
fi
sleep 0.1
done
echo -e "\n$serviceName did not terminate within $maxShutdownTime seconds, sending SIGKILL..."
kill -s KILL $pid || return 1
local killWaitTime=15
for ((i=0; i<killWaitTime*10; i++)); do
checkProcessIsRunning $pid
if [ $? -ne 0 ]; then
rm -f $pidFile
return 0
fi
sleep 0.1
done
echo "Error: $serviceName could not be stopped within $maxShutdownTime+$killWaitTime seconds!"
return 1; }

function startService {
getServicePID
if [ $? -eq 0 ]; then echo -n "$serviceName is already running"; RETVAL=0; return 0; fi
echo -n "Starting $serviceName   "
startServiceProcess
if [ $? -ne 0 ]; then RETVAL=1; echo "failed"; return 1; fi
echo "started PID=$pid"
RETVAL=0
return 0; }

function stopService {
getServicePID
if [ $? -ne 0 ]; then echo -n "$serviceName is not running"; RETVAL=0; echo ""; return 0; fi
echo -n "Stopping $serviceName   "
stopServiceProcess
if [ $? -ne 0 ]; then RETVAL=1; echo "failed"; return 1; fi
echo "stopped PID=$pid"
RETVAL=0
return 0; }

function checkServiceStatus {
echo -n "Checking for $serviceName:   "
if getServicePID; then
echo "running PID=$pid"
RETVAL=0
else
echo "stopped"
RETVAL=3
fi
return 0; }

function main {
RETVAL=0
case "$1" in
start)                                               # starts the Java program as a Linux service
startService
;;
stop)                                                # stops the Java program service
stopService
;;
restart)                                             # stops and restarts the service
stopService && startService
;;
status)                                              # displays the service status
checkServiceStatus
;;
*)
echo "Usage: $0 {start|stop|restart|status}"
exit 1
;;
esac
exit $RETVAL
}

main $1